Answer:
Of course, technician B is the smarter one!
Explanation:
Water molecules attract each other, and the oil molecules also stick together. That causes oil and water to form two separate layers.
Because water molecules are denser than oil, they sink to the bottom, leaving oil sitting on top of the water.
Now, many fuel systems are designed in such a way that the suction pipe is located at the base of the tank. Given the above, it is very easy to see why water to a great degree of probability will be drawn into the system when the fuel level is low.
Cheers!